Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Green Cobalt(II) hydroxide in D2O
tylerngo
Harmless
*




Posts: 4
Registered: 11-10-2018
Member Is Offline


[*] posted on 11-10-2018 at 04:51
Green Cobalt(II) hydroxide in D2O


I reacted Potassium metal with Deuterium oxide in order to yield a basic solution of Potassium deuteroxide. I then added Cobalt(II) chloride to precipitate Cobalt(II) deuteroxide. It has been 2 days already and my precipitate is still green. Why do you think this is?
View user's profile View All Posts By User
j_sum1
Administrator
Thread Moved
11-10-2018 at 05:15
fusso
International Hazard
*****




Posts: 1922
Registered: 23-6-2017
Location: 4 ∥ universes ahead of you
Member Is Offline


[*] posted on 11-10-2018 at 07:41


Why you want to make Co(OD)2?



View user's profile View All Posts By User
Boffis
International Hazard
*****




Posts: 1836
Registered: 1-5-2011
Member Is Offline

Mood: No Mood

[*] posted on 15-10-2018 at 06:37


How did you add the cobalt chloride? If it was in aqueous solution or even as the solid hydrated salt will you not get hydrogen/deuterium partitioning? Or did you use a more sophisticated aprotic solvent system or anhydrous CoCl2 dissolved in deuterium oxide? Without more details we can't really help you. Furthermore how do you know your product is simple Co(OH)2?

natural cobalt calcium hydroxide arsenate (cobaltaustinite) is dark green whereas hydrated cobalt calcium arsenates are deep pink to magenta coloured. Its all to do with what ligand the cobalt is coordinated with. I would be very surprised if deuterium oxide caused a significant chromatic shift compared to water. I think that it is more likely that the potassium deuteroxide solution is so concentrated that you have precipitated an anhydrous product which is inherently green.
View user's profile View All Posts By User

  Go To Top